A sound delivery assembly for hearing aid, communication system or multimedia system is primarily configured to achieve high quality acoustic performance. It is also desired that the structure of the sound delivery assembly maintain in manufacture a designed user comfort in wearing it because he/she wants to use it for an extended time.
High quality acoustic performance is achieved by high efficiency and high fidelity of the sound delivery system. Efficiency of a sound delivery system is determined by the size of a speaker element and the distance to the entrance of the ear canal from the end of the sound delivery assembly. Fidelity of a sound delivery system is determined by a number of factors including the size of the speaker element and the length of a sound tube to deliver sounds.
So far, there are two primary types of sound delivery tools. One of them adopts an occluding earset structure such as an earmuff, an occluding earbud, or an occluding earmold. The other type adopts a non-occluding earset structure.
An ear-occluding structure such as the earmuff type achieves high quality acoustic performance because the size of a speaker element can be relatively large. Other ear-occluding structures such as the earbud and the earmold sound delivery systems also achieve high quality acoustic performance because the sound is delivered into the ear canal at the entrance of the ear canal and because the sound pressure is sealed in by the occlusion, thereby easily producing good bass and high sound level. Thus, small speaker drivers can be used with occluding systems. However, it is not physically comfortable for a user to occlude the ear for an extended period for two reasons: the physical discomfort due to pressure on the tissue required to get a good seal as the jaw and jaw muscles move and change the canal shape, and due to the disturbing and uncomfortable nature of the sound of the user's own voice (bassy and too loud) and audibility of bodily sounds (heart beat, blood flow, chewing sounds, clearing throat, etc.). Another reason for the user's discomfort is that a user has difficulty in hearing sounds other than that delivered by the sound delivery assembly. Lack of hearing the background sounds makes a user feel isolated from his surroundings and uncomfortable. Particularly, when a user uses a mobile phone or communicates with a computer or multimedia, he/she needs to hear the surrounding sounds for safety or as a necessary part of the experience.
Where the ear is not occluded, a user can hear surrounding sounds in addition to delivered sounds. Conventional non-occluding earsets are coupled with a relatively long sound tube for delivering sounds. They do not achieve high quality acoustic performance because their efficiency and fidelity are not high. Various structure of non-occluding earsets have been designed, however, they are not adjustable for each individual ear anatomy so that some users feel uncomfortable tension to the ear in wearing the earset or the earset provides compromised performance for some users due to the ill fit of the device.
U.S. Pat. No. 6,009,183 by Taenzer presents an ambidextrous sound delivery system. This sound delivery system uses a tube for delivering sounds. It has an ambidextrous feature provided by rotating the tube at its axis. However, the long tube affects the sound fidelity so that substantial additional form elements need to be included. Additionally, the tube terminates in the ear canal so that the accommodation of different ear sizes has to be done by flexing the tube creating uncomfortable pressure on the canal wall. Further, since the entrance to the ear canal has hair, some users report that an unbearably uncomfortable tickling sensation is produced by the tube.
U.S. Pat. No. 6,438,245 “Hearing Aid Communications Earpiece” shows an above-the-ear microphone for pickup of the user's own voice. U.S. Pat. Nos. 6,021,207 “Wireless Open Ear Canal Earpiece” and 6,181,801 “Wired Open Ear Canal Earpiece” show devices providing sound delivery to the ear canal in a non-occluding manner.
U.S. Pat. No. 5,659,156 by Mauney presents an earmold for two-way communications devices. This earmold is a non-occluding one designed to securely hold the earmold in the ear and deliver sounds at the entrance of the ear canal. However, this earmold has to be configured to fit each individual and must also be configured to separately fit right and left ears. It is not adjustable for the anatomy of each individual or ear.
An object of the present invention is to provide a earset assembly having a structure that easily fits to almost all people's either right or left ear and allows a user to wear it with great comfort on the ear for an extended period.
Another object of the present invention its to provide an earset subassembly which creates and assures good sound performance for almost all ears.
Another object of the present invention its to provide an earset subassembly which facilitates ease and flexibility in manufacturability of the assembly.
Another object of the present invention its to provide an earset subassembly which facilitates ease of testing of the assembly during manufacture.